Modern Physics: Physics 251/252

Lecture Notes and Tentative Schedule

Week 1: 8/31 l1 , Taylor Series: formulas, lecture
Week 2: 9/5 l2 l3 hw1 , hw1_sol, lab sample + error anal, latex file for labs (if you use latex)
Week 3: 9/12 l4 l5 hw2 , hw2_sol,
Week 4: 9/19 l6, l78, hw3 hw3_sol
Week 5: 9/26
Week 6: 10/03 l9 l10 hw4 hw4_sol
Week 7: 10/10 First Practice Test , solutions, Second Practice Test , solutions, Formulas , exam1, exam1_solutions exam1_grades
Week 8: 10/17 hw5, hw5_sol , l11_intro, l11,
Week 9: 10/24 hw6 hw6_sol , l12 l13 ldebroglie slides Group Velocity
Week 10: 10/31 hw7, hw7_sol l14 l15
Week 11: 11/07 hw8 solutions l16 l17 l18 complex quiz material , quiz in recitation next week. solutions , quizzes for both recitations+answers
Week 12: 11/14 hw9 hw9 solutions l19 l20, lsho - slides (Use Adobe Reader not Preview), SHO Table l21 First Practice Test , solutions, Second Practice Test , solutions,
Thanksgiving: 11/21
Week 13: 11/28 l21 l22 l22 slides hw10 hw10_sol
Week 14: 12/05 l23 (last lecture on exam) l23 slides

Tentative Lab Schedule

This schedule is subject to change

Week 1: 8/31 No Lab
Week 2: 9/5 No Lab: Labor Day
Week 3: 9/12 Lab1: Michelson Morley
Week 4: 9/19 Lab2: E/M Ratio
Week 5: 9/26 Lab3: Millikan
Week 6: 10/03 Makeup
Week 7: 10/10 Lab 4: Photoelectric Effect
Week 8: 10/7 Lab 5: Standing Waves
Week 9: 10/24 Lab 6: Scattering Angles
Week 10: 10/31 Makeup
Week 11: 11/07 Lab 7: Hydrogen Spectrum
Week 12: 11/14 Lab 8: Bragg Scattering
Thanksgiving week No Lab
Week 14: 11/28 Makeup Numerical Lab
Week 13: 12/05 Numerical Lab

Course Organization


This course attempts to introduce the physics of the time period from 1905 to about 1930. Thus the name modern physics is perhaps a misnomer since it is more than seventy years old. Perhaps "introduction to a weird universe" would be a better title. In 1905 Albert Einstein (pictured below) deduced some aspects of this weird universe through a deep understanding of electricity and magnetism and classical mechanics.

The course will first introduce the basic notions of special relativity. Subsequently we will turn to quantum mechanics introducing the de Broglie wavelength and the photoelectric effect. Then we will study the Bohr model with an emphasis on estimates. Then we will investigate in detail quantum mechanics in one dimension. After this work we will begin to discuss the hydrogen atom and atomic structure .

Additionally this course will try to transition young scientists from elementary classes to more advanced junior and senior level courses. Fourier series will be introduced and Taylor series used constantly to develop an intuition for approximation and estimation.

Lecture Instructors:

Assist. Professor Derek Teaney: derek.teaney

Derek Teaney
Department of Physics & Astronomy
PO Box 3800
Stony Brook, NY 11764-3800

Office: Physics C-135

(631)632-4489, Fax 9718

Laboratory Assistant and Grader

Wang, Yihong: yihong.w2 (see schedule)
Aungshuman, Zaman: azaman (see schedule)
Jaehong Kim (grader)

Grade Determination

The grading will be based roughly on the following table. I reserve the right to change these proportions (within reasonable limits) as the course progresses. My intent of course is to follow these guidelines.

Exam 1 30/15%
Exam 2 30/15%
Final 40%
Homework/Recitation 15%

The 30/15% means that the highest of the two in class exams will be given 30% and the lowest of the two in class exams will be given 15%. There will be no makeups for the in class exams. If you miss an exam because, e.g. your car breaks down, this will count as your low score and will be dropped. In this way the bad things that happen in life will set you back, but will not knock you down!

Homework and Recitation

Recitation/homework is a major component of this course. Experience has shown that students who do not do the homework will not know what to do on the exams. Homework will be assigned in class (usually on Thursday) and collected in class (usually Thursday). Only a portion of the homework will be graded.

During recitation the homework will be reviewed, and at the end a quiz will be given which will most often be taken from the assignment. The quiz is not intended to be hard. Almost always the problem actually on the quiz will be discussed in the recitation just before the short test and the necessary formulas are left on the board!

Some number of quizzes will be dropped (at least one and perhaps two.)


Class Meetings

The class meets Tuesday and Thursday in S240 in the basement of the Mathematics Building


Recitation hours are on Wednesday

  1. R01 -- M 11:45--12:40 in S240-Mathematics Basement
  2. R02 -- W 11:45--12:40 in S240-Mathematics Basement


All labs are in Physics A133

  1. L01 -- Monday, 12:50--2:50
  2. L02 -- Monday, 3:50--5:50
  3. L03 -- Monday, 6:00--8:00

Office Hours

Please feel free to contact me at anytime. My official office hours are,

Final Exam

The final is worth 40% of your grade and is on Wednessday, December 14 from 2:15--4:45 p.m.

Physics 252 -- The Laboratory

PHY 252 (The Lab) is a separate course from PHY 251, but students earn a common grade in PHY 251 and PHY 252. PHY 252 is required and must taken concurrently with PHY 251.

Labs give you a chance to get a glimpse at some of the classic experiments which have either led to or confirmed important understandings in modern physics.

The laboratory manual will be provided week-by-week on the course web page. Print out a copy for yourself before each lab.


Other Items

The Text Books

  1. The book for relativity is Spacetime Physics, by Taylor and Wheeler.
  2. The book for quantum mechanics is Quantum Physics of Atoms, Molecules, Solids, Nuclei, and Particles by Robert Eisberg and Robert Resnick.
Both of these books are considered "classics" of a sort and get very high ratings at

Academic Integrity

Please read the statement on the undergraduate physics web page on student ethics and academic honesty. We will apply those standards to this class.

Each student must pursue his or her academic goals honestly and be personally accountable for all submitted work. Representing another person's work as your own is always wrong. Faculty are required to report any suspected instances of academic dishonesty to the Academic Judiciary. Faculty in the Health Sciences Center (School of Health Technology & Management, Nursing, Social Welfare, Dental Medicine) and School of Medicine are required to follow their school-specific procedures. For more comprehensive information on academic integrity, including categories of academic dishonesty, please refer to the academic judiciary website at

Americans with Disabilities Act

If you have a physical, psychological, medical or learning disability that may impact your course work, please contact Disability Support Services, ECC (Educational Communications Center) Building, room128, (631) 632-6748. They will determine with you what accommodations, if any, are necessary and appropriate. All information and documentation is confidential.

Critical Incident Management

Stony Brook University expects students to respect the rights, privileges, and property of other people. Faculty are required to report to the Office of Judicial Affairs any disruptive behavior that interrupts their ability to teach, compromises the safety of the learning environment, or inhibits students' ability to learn. Faculty in the HSC Schools and the School of Medicine are required to follow their school-specific procedures.


You do not have to come to class. But please try. During recitation a quiz will be given and homework will from be collected from time to time and so attendance is important (though some number of quizzes will be dropped).